Books: Post-Newtonian

If you are not a mathematician, stick to your muttons. So hints
Astronomer Sir James Jeans. "It is true, in a sense somewhat
different from that intended by Galileo, that 'Nature's great book is
written in mathematical language.' So true is it that no one except a
mathematician need ever hope fully to understand those branches of
science which try to un ravel universethe theory fundamental of
nature of relativity, the the theory of quanta and the
wave-mechanics."